In a week of special coverage, ITV News is taking a closer look at how widespread starvation is threatening countriesin parts of the Middle East and Africa.
The Head of the World Food Programme in London Greg Barrow writes about how children and the elderly are most at risk.
There is nothing worse than seeing a small child slip away because they cannot get enough of the right food to eat.
Starvation is an ugly and unforgiving end to life that occurs when the body shuts down due to a lack of proper nutritious food.
With famine already declared in South Sudan and the prospect of famine emerging in Nigeria, Yemen and Somalia, the outlook for the very young in a swathe of countries across sub-Saharan Africa and into the Middle East right now is grave.
In every famine, there is a grim and inescapable statistical probability that the very old and the very young will suffer first and many may not see this one through.
If any young child is deprived of healthy, nutritious food, the outcome is always going to be bleak.
In the harsh conditions where many are living in the four countries worst affected by food shortages, they will succumb frighteningly quickly.
To survive, it is essential that children get the food they need to grow strong and thrive in later life.
There is a critical 1000-day window, from the moment a child is conceived in the womb to the point at which he or she reaches her second birthday, during which good nutrition helps to lay down the building blocks for future physical and intellectual development.
Deprive any child of the vitamins and minerals that they need in this moment of their life and the effects are irreversible.
Both physical and intellectual development will be affected.
The technical term for this failure to grow and thrive is “stunting,” something that Charles Dickens wrote about when describing the hungry and abandoned urchins who used to roam the streets of Victorian London.
The tragedy we now face is that while stunting is something confined to historical novels from the London of a century and a half ago, it is a clear and present threat to the lives of children in north-eastern Nigeria, South Sudan, Yemen and Somalia, today.
Providing for the urgent needs of these children is at the forefront of the international relief effort now underway.
Working with other agencies on the ground, the World Food Programme is providing highly nutritious food products in the form of fortified peanut pastes that can help children on the road to recovery if they are suffering from the effects of under nutrition.
They look and taste like peanut butter and come in little foil packets that parents can open and feed to their children on the spot.
In all of the four countries worst affected by hunger needs, not only are they a life-saver but they can also ensure that the children avoid the longer term impact of under nutrition in later life.
To support the World Food Programme’s work text "FOOD" to 70500 to donate £5 to help build a world without hunger or donate online.
The views of Greg Barrow do not necessarily reflect those of ITV News